Exhibit 10.627

SUPPLEMENTAL PENSION AGREEMENT

AGREEMENTmade and entered into as of July 20, 2004 by and between CHIRON CORPORATION, a Delaware
corporation, and WILLIAM G. GREEN ("Green") in order to memorialize the deferred compensation/supplemental retirement arrangement referenced in the Chiron offer letter to Green dated
September 26, 1990 and formally document the terms and conditions governing the supplemental pension benefits accrued and accruable by Green over his period of service with Chiron, and to
effect certain revisions to those terms and conditions.

1.Provision of Benefit.    In consideration of services to be performed by Green, Chiron shall, in addition to other
compensation agreed to from time to time, provide to Green a pension benefit in an amount determined under Section 5, to be paid in a form determined under Section 6 commencing at a time
determined under Section 4. The benefit under this Agreement shall be fully vested and nonforfeitable at all times.

2.Nature of Benefit.

a.Unsecured Obligation.Except as provided in subsection b, the benefit to be provided under this Agreement is
an unfunded, unsecured obligation of Chiron. Green, his Spouse, and their beneficiaries, heirs, successors, and assigns shall have no secured interest in, or secured claim against, any property or
assets of Chiron, and no assets of Chiron shall be held under any trust for the benefit of Green, his Spouse, or their Beneficiaries, heirs, successors or assigns or be considered in any way as
collateral security for the fulfillment of the obligations of Chiron under this Agreement.

b.Establishment of Trust.Notwithstanding subsection a, upon written request of Green, Chiron shall establish
an irrevocable trust which shall provide, subject to the claims of general creditors of Chiron in the event Chiron becomes insolvent, that (i) the assets thereof shall be held for the exclusive
purpose of providing benefits under this Plan, (ii) Chiron shall, in its discretion, contribute from time to time to such trust the amount actuarially determined as necessary to fund the
expected benefits hereunder. Any trust established under this subsection shall be substantially in the form set forth in Rev. Proc. 92-64 and/or then current IRS guidance supplementing or
replacing Rev. Proc. 92-64. The trustee under such trust shall be an institution unaffiliated with Chiron and Green, and assets of the trust shall be invested by such trustee in accordance
with guidelines agreed upon by Green and Chiron and incorporated in such trust agreement.

3.Definitions.

a.Actuarial Equivalent:An amount of benefit in the appropriate form (determined in accordance with
Section 6) which is equivalent to the dollar amount determined under Section 5b on the basis of an assumed interest rate and a mortality table. Such interest rate shall be the applicable
rate in effect under Section 417(e) of the Code determined as of the time benefits commence, and such mortality table shall be the applicable mortality table in effect under
Section 417(e) of the Code determined as of the time benefits commence.

b.Chiron:Chiron Corporation, a Delaware corporation, and any successor to all or a major portion of the assets
or business of Chiron Corporation.

c.Code:The Internal Revenue Code of 1986 as amended from time to time.

d.ERISA:The Employment Retirement Income Security Act of 1974 as amended from time to time.

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e.401(k) Plan:    The Chiron Corporation 401(k) Plan as in effect from time to time.

f.Spouse:Green's lawful spouse (or surviving spouse) on the date payment of benefits commences under
Section 4.

4.Commencement of Benefit.

a.Time of Commencement.



b.Actuarial DeterminationAt the time the benefit is to commence under subsection a, an enrolled actuary
mutually agreeable to Green and Chiron shall determine the Actuarial Equivalent, in the applicable form under Section 6, of the amount of benefit set forth in Section 5.

c.Initiation of Payment.Actual benefit payments retroactive to the commencement date specified in subsection
4.a shall be made within 30 days after such date or, if not made within 30 days, shall be made on the 90th day after such date. Notwithstanding the foregoing, the actual commencement
date for all or a portion of the benefit payments to which Green is entitled hereunder may be further deferred beyond the applicable 30- day or 90-day period to the extent
necessary to avoid any adverse income tax consequences to Green which might otherwise result by reason of subsequent changes to the federal income tax laws and regulations governing
non-qualified deferred compensation plans.

5.Amount of Benefit.

a.In General.The amount of the benefit hereunder shall be the amount of the annuity benefit, in the applicable
form under Section 6, which is the Actuarial Equivalent (as of the date benefits commence under Section 4) of the amount determined under subsection b of this Section 5.

b.Computation.The amount determined under this subsection is the sum of (1), (2), (3) and (4), where:



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c.Time of Accrual.Amounts under this Section 5 for a particular calendar year are deemed to accrue on
the last day of such year, except that with respect to the year in which benefits commence, such amounts are deemed to accrue on the date on which benefits commence.

d.Interest.The applicable interest rate for all compounding periods ending on or before May 31, 2004
shall be seven percent (7%) per annum. The applicable interest rate for all compounding periods beginning on or after June 1, 2004 and ending on the actual commencement date of benefits
hereunder shall be six percent (6%). However, should Green elect pursuant to subsection 4.a(ii) to defer the commencement date of his benefit beyond the date that benefit would have otherwise
commenced pursuant to subsection 4.a(i) in the absence of that election, then for all compounding periods which occur during that extended deferral period, the interest rate shall be six (6%)
percent.

6.Form of Benefit.

a.Green and Spouse Both Surviving.If both Green and his Spouse are alive on the date benefits commence under
Section 4 hereof, benefits shall be paid in the form of a joint and survivor annuity under which benefits shall commence at the time determined under Section 4 hereof and shall
thereafter be paid monthly until the month in which the death of Green occurs, after which month no further benefits shall be paid; provided, however, that if Green's Spouse is surviving at his death,
she shall thereupon be entitled to a monthly benefit until the month in which her death occurs which shall be equal to 50% of the monthly benefit payable during Green's lifetime. After the month in
which the death of Green's Spouse occurs, no further benefits shall be paid.

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b.Green Surviving.If Green is alive and unmarried on the date benefits commence under Section 4 hereof,
benefits shall be paid in the form of a single life annuity under which benefits shall commence at the time determined under Section 4 hereof and shall thereafter be paid monthly until the
month in which the death of Green occurs, after which month no further benefits shall be paid.

c.Spouse Surviving.If, on the date benefits commence under Section 4 hereof, Green is deceased but is
survived by a Spouse, benefits shall be paid in the form of a single life annuity under which benefits shall commence as of the first day of the month in which Green's death occurs and shall
thereafter be paid monthly until the month in which the death of such Spouse occurs, after which month no further benefits shall be paid.

d.Neither Green or Spouse Surviving.If, on the date benefits commence under Section 4 hereof, Green is
deceased and is not survived by a Spouse, benefits shall be paid in the form of a lump sum to such one or more beneficiaries as he may designate in a signed writing referring specifically to this
Agreement and filed with Chiron prior to his death. In the event no such beneficiary designation is filed prior to his death, then the sum shall be paid to those persons entitled to succeed to his
separate property under the laws of the State of California then in effect if Green were then a resident of such state and died intestate.

e.Annual Payment Option.At the sole election of Chiron, one or more monthly annuity payments otherwise due and
payable to Green or his spouse during a calendar year may instead be paid in one annual installment before the end of that calendar year. However, such annual installment shall also include an
interest component on each deferred monthly annuity payment at the rate of six percent (6%) per annum for the period between the date that monthly annuity payment would have otherwise become due and
payable to Green or his spouse in the absence of Chiron's payment election hereunder and the actual date of payment.

7.Construction of Effectiveness.

a.Construction.The headings and subheadings of this Agreement are inserted for convenience of reference only
and are not to be considered in the construction of this Agreement. Unless the context clearly indicates otherwise, words used in the singular shall include the plural, the plural may be read as the
singular, and the masculine shall include the feminine.

b.Governing Law.This Agreement shall be construed, administered, and governed in all respects in accordance
with the laws of the State of California except to the extent preempted by federal law.

c.Severability.If any provision of this Agreement shall be held by a court of competent jurisdiction to be
invalid or unenforceable, the remaining provisions shall continue to be fully effective.

d.Entire Agreement; Amendment.This Agreement embodies the entire agreement and understanding of the parties
hereto with respect to the subject matter hereof, and supersedes all prior and contemporaneous agreements and understandings, oral or written, relative to said subject matter. No amendment,
modification, or waiver of any provision of this Agreement, nor consent to any departure herefrom, shall be effective unless in writing and signed by both parties.

e.Nonassignability.Neither Green nor any other person shall have any right to commute, sell, assign, transfer,
pledge, anticipate, mortgage or otherwise encumber, hypothecate or convey in advance of actual receipt the amounts, if any, payable hereunder, or any part thereof. No part of the amounts payable
shall, prior to the actual payment, be subject to seizure or sequestration for the payment of any debts, judgments, alimony or separate maintenance owed by Green or any other person nor be
transferable by operation of law in the event of any person's bankruptcy or insolvency.

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f.Binding Effect.The terms and provisions of this Agreement shall be binding on and inure to the benefit of
Green and Chiron and the successors and assigns of each.

g.ERISA Exemptions.The parties intend that this Agreement be exempt from Part 4 of Title I of ERISA by
virtue of Section 401(a)(1) of ERISA.

8.Other Provisions.

a.Administration.Any election, designation, or other communication by Green to Chiron hereunder shall be given
to the Chief Financial Officer of Chiron.

b.Exercise of Rights.After the death of Green any rights or elections hereunder shall be exercisable by his
Spouse or, if there is no Spouse, by his executor or other duly appointed personal representative.

c.No Right to Employment.Nothing in this Agreement shall give to Green the right to be retained in the employ
of Chiron nor any rights or interest in the benefits provided hereunder other than as herein specifically provided.

d.Discharge of Claims.Any payment to Green, his Spouse, any beneficiary, or the legal representative of any
person, in accordance with the terms of this Agreement, shall to the extent thereof be in full satisfaction of all claims such person may have against Chiron hereunder. Chiron may require such payee,
as a condition to such payment, to execute a receipt and release therefor in such form as shall be determined by Chiron.

IN WITNESS WHEREOF,the parties have executed this Agreement as of the date first above written.

| |  | CHIRON CORPORATION
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| |  | By:               
| |  | Title:            
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